import pigpio
import time
import logging
import json

from wiegand import decoder

class gate:
  def __init__(self, pi, relay_pin):
    self.pi = pi
    self.relay_pin = relay_pin

    # set the pin to high to keep the gate locked
    pi.write(relay_pin, 1)

  # unlocks the gate for a number of seconds defined by timeout
  def unlock_gate(self, timeout):
    self.pi.write(self.relay_pin, 0)
    time.sleep(timeout)
    self.pi.write(self.relay_pin, 1)

def load_secrets():
    with open("./secrets.json") as secrets:
        return json.loads(secrets.read())

if __name__ == "__main__":
  secrets = load_secrets()
  pi = pigpio.pi()
  gate = gate(pi, 4)

  current_code = ""
  def callback(bits, value):
    global current_code
    # indicates keypad press
    if bits == 4:
      current_code = current_code[-3:] + str(value)
      if len(current_code) == 4:
        # check if we have a valid code
        if current_code in secrets['codes']:
          gate.unlock_gate(5)
        current_code = ""
    # indicates a card swipe
    elif bits == 37:
      current_code = ""
      str_value = str(value)
      if str_value in secrets['cards']:
        gate.unlock_gate(5)

    logging.info("bits={} value={}".format(bits, value))

  w = decoder(pi, 2, 3, callback)
  time.sleep(1000)
  w.cancel()
  pi.stop()